Although it can be used for any desired arrangements for connection of pipes, the present invention and the problems on which it is based will be explained in more detail with respect to pipes for carrying dirty water away in an aircraft.
There is a requirement in aircraft to carry dirty water, in particular from washing basins in the cabin, away to the exterior, that is to say into the atmosphere. Pipelines are provided for this purpose which are composed of a plurality of pipes connected to one another, in particular in order to comply with the geometric requirements in the aircraft. An arrangement must accordingly be provided for fluid-tight connection of the respective pipe ends of the pipes.
Lightning strikes, for example, can result in static electrical charging of pipes such as these which, in particular, are produced from stainless steel or titanium, and thus in an electrical potential difference between the pipes and the aircraft structure surrounding them. A potential difference such as this can have hazardous consequences, for example, incorrect measurements or destruction of electronics on board the aircraft. It is therefore necessary to dissipate the electrical charge from the pipes. This is generally achieved by connecting the pipes to one another by means of a plurality of electrical conductors and by dissipating the electrical charge to the exterior, that is to say into the atmosphere, at a specific point on the aircraft, by means of a further electrical conductor.
In consequence, there is a requirement for two pipes to be connected to one another not only such that they are fluid-tight but also electrically conductively. One approach that is known to the applicant provides an arrangement 1 as illustrated in FIG. 7. This arrangement 1 has a collar 2 with two holding sections 3, 4 in which a first and a second pipe end 5, 6, respectively, can be held in a fluid-tight manner. In addition, earth clamping rings 7, 8 are attached to the first and second pipe ends, at a distance from the collar 2. Those points on the pipe ends 5, 6 to which the earth clamping rings 7, 8 are fitted must then be treated with a specific sealing agent in order to prevent the ingress of moisture, and thus contact corrosion between the earth clamping rings 7, 8 and the first and second pipe ends 5, 6. An earth connector 9, that is to say an electrical conductor, is electrically conductively attached to the earth clamping rings 7, 8 by means of screw connections 10, 11 at each of its ends.
This approach disadvantageously results not only in a large amount of manual effort, but also in considerable weight.
The features of the precharacterizing clause of claim 1 are known both from GB 588 072 A and GB 566 279 A.